1. Technical Field
The present application is for a rack, and more particularly, to a rack for mounting a communication system including communication apparatus and the components of that apparatus.
2. Background Art
Today, the art of communication involves equipment that requires many components. As each component (e.g., switches, transmitters, boards, and modular elements) has a chance of being manufactured incorrectly, having more components increases the chance of a manufacturing error per equipment. Therefore, reducing the chance of a manufacturing error is important. One way of reducing the chance of a manufacturing error is to reduce the overall number of components. With fewer overall parts, manufacturing involves a lesser number of assembly steps for a reduced number of parts, thus reducing the chance for occurrence of an assembly error. Another way of reducing the chance for a manufacturing error is to have fewer number of types of components. With fewer types of components, the manufacturing involves less component fabrication, thus reducing the chance of component fabrication error. This goal of reducing the manufacturing error is balanced by the need to have equipment that is just as functional as any other equipment. The challenge is to have equipment that has a smaller chance of being manufactured incorrectly, but is just as functional as other equipment of its type.
In the past, a rack for communication apparatus consisted of many components, such as walls, nuts, bolts, and other items. Constructing such a rack according to contemporary practice requires a large number of dissimilar components. Further, assembling such components requires a large set of the fasteners such as screws, bolts, or rivets essential for joining the parts together. According to conventional practice, a sub-rack structure with separate shelves and a large number of locking pieces is required for installation of the various necessary components, a bottleneck on productivity. Comparable problems are attributable to racks and card cages assembled from stamped, punched, and slotted sheet material as represented by, for example, the Electrical Circuitry Support Apparatus of Wadell, U.S. Pat. No. 4,894,753. Due to these requirements for assembly of shelves, the product quality is at risk of deterioration while the per unit cost is increased. Also, the performance of the communication system can be impaired. In a communication system, a PBA board connector and a backboard connector should be precisely coupled to assure continuous long-term reliable communication. In a conventional sub-rack structure with shelves, because various components are assembled by a set of locking fasteners, the cumulative effect of out of tolerance parts all too often exceeds the tolerance limit of the overall system.
Examples of the art, such as Zell (Cabinet for the Acceptance of Electrical Card Cages, U.S. Pat. No. 5,229,924, Jul. 20, 1993) teach a cabinet system of one or more card cages. Hershberger et al. (Apparatus for Shielding an Electrical Circuit from Electromagnetic Interference, U.S. Patent No. 4,829,432, May. 9, 1989) proposes to join a ground player layer with a solder joint while Hosking (Electronic Equipment Rack Interconnection System, U.S. Pat. No. 4,686,608, Aug. 11, 1987) discusses a rack assembly using a mating connector assembly. Constructing such racks according to contemporary practice requires a large number of dissimilar components. Moreover, according to contemporary practice, such racks do not have a single part that holds all other parts together.